Clavierübung is a set of 24 preludes, each and all of which are intended to be equally idiomatic to the piano, organ, and harpsichord. The work was begun in November 2003 and completed the following month. Each piece is a depiction of one of 24 historical modalities in the old "major-minor" key system of 18th–19th-century practice, and each piece is notated in one of 24 different time-signatures. The individual titles — prelude, interlude, postlude — are mere character names with no intrinsic significance; however, they serve to underscore a possible and desirable delineation of the work into eight parts of three movements each. When treated in this way each three-movement group presents a different scheme of tempo and dynamics, e.g., fast-fast-fast, slow-slow-fast, and forte-forte-forte, piano-piano-forte, etc. Although no truly original material is utilized anywhere throughout the work, some pieces are overt homages to specific historical personages such as Louis Vierne, Johann Strauss, Max Reger, Frederic Chopin, Ludwig van Beethoven, and Johann Sebastian Bach.
—Frank Morana